Switch to HTML5 is slowly happening. Popular HTML5 Sublime video player now supports "fall back to Flash Mode".
As quoted from the RWW article, "This means that when a web surfer using a browser that doesn't support HTML5 visits a page that uses the player, it will automatically switch over (aka "fall back") to Adobe Flash, the plugin-based technology that older, non-HTML5 web browsers use. Why is this important? In addition to providing a path to move from one technology to the next, a transition that will take years at best, SublimeVideo could ease the workload for developers tasked with creating web pages that the entire web audience can access"
